US4604279A - Process for producing ozone - Google Patents
Process for producing ozone Download PDFInfo
- Publication number
- US4604279A US4604279A US06/773,030 US77303085A US4604279A US 4604279 A US4604279 A US 4604279A US 77303085 A US77303085 A US 77303085A US 4604279 A US4604279 A US 4604279A
- Authority
- US
- United States
- Prior art keywords
- ozone
- equalizing tank
- silica gel
- pressure swing
- pressure
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 title claims abstract description 64
- 238000000034 method Methods 0.000 title claims description 18
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 19
- 239000001301 oxygen Substances 0.000 claims abstract description 17
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 17
- 239000000741 silica gel Substances 0.000 claims abstract description 17
- 229910002027 silica gel Inorganic materials 0.000 claims abstract description 17
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 15
- 239000007789 gas Substances 0.000 claims description 20
- 238000003795 desorption Methods 0.000 claims description 19
- 238000001179 sorption measurement Methods 0.000 claims description 6
- 239000006096 absorbing agent Substances 0.000 claims description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 12
- 239000002609 medium Substances 0.000 description 7
- 238000006243 chemical reaction Methods 0.000 description 5
- 230000002000 scavenging effect Effects 0.000 description 3
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 2
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 239000012429 reaction media Substances 0.000 description 2
- 239000006163 transport media Substances 0.000 description 2
- 239000002253 acid Substances 0.000 description 1
- 239000003463 adsorbent Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 231100001261 hazardous Toxicity 0.000 description 1
- 150000002484 inorganic compounds Chemical class 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 150000002926 oxygen Chemical class 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B13/00—Oxygen; Ozone; Oxides or hydroxides in general
- C01B13/10—Preparation of ozone
Definitions
- the present invention pertains to a process for producing ozone for the treatment of materials, according to which process the ozone is produced from oxygen in an ozone generator.
- Ozone is an excellent oxidant for many organic and inorganic compounds. It is possible, for example, to treat undesirable components present in water to discolor or detoxify them or to render them biodegradable or flocculable.
- the oxidizing effect of ozone is utilized in chemistry, e.g., to produce acid. Pulp is bleached with ozone.
- the surface of plastics can be modified by ozone treatment. Gases can also be reacted with ozone; for example, nitric oxide can be oxidized with ozone.
- ozone is produced in ozone generators by silent electric discharge from air or pure oxygen. Since only part of the oxygen fed into the ozone generator is transformed into ozone, the nonconverted oxygen must be separated from the ozone and recycled into the ozone generator in the case of ozone generation from pure oxygen for economic reasons. This oxygen separation can be carried out in pressure swing absorbers.
- the ozone is adsorbed by silica gel in these plants during the adsorption phase under slightly increased pressure.
- the ozone is subsequently desorbed under a somewhat lower pressure during a desorption phase.
- a scavenging gas is used for the desorption; however, it has the disadvantage of diluting the desorbed ozone.
- a process in which the desorption is carried out under lower than atmospheric pressure is known from DE-OS No. 32 30 922.
- the vacuum is generated, e.g., by a water jet gas compressor.
- the ozone is drawn off from the pressure swing adsorber without dilution and is mixed with the water of the water jet gas compressor. the ozone can undergo the intended reactions even in this water, if so desired.
- the fluctuations in concentration are caused by the decreasing ozone loading of the silica gel during the desorption phase.
- the concentration is also influenced by residual oxygen which has been adsorbed in the silica gel and in the free and pore volumes of the silica gel adsorber during the adsorption process, because it is also present in the desorbed gas.
- Such variations in concentration and pressure are irrelevant for many applications. However, they can have an adverse effect on the intended reactions with ozone when the reaction and hold times are short.
- the present invention therefore has as its object improving the process known from DE-OS No. 32 30 922 in such a way that the ozone desorbed under lower than atmospheric pressures can be fed into the vacuum-generating machine under constant pressure and at constant concentration.
- the process according to the present invention has the advantage that the pressure and concentration peaks occurring in the desorbed gas can be compensated and equalized.
- the pressure and concentration can be maintained below hazardous limit values at low cost.
- uniform ozone concentrations permit shorter hold times of the reaction partners in the reactions of ozone.
- the limit values to be observed are 0.6 bar (absolute) for the pressure and 160 g/l technological cubic meter of gas for the concentration.
- the single FIGURE illustrates an example of the present invention in which the lower than atmospheric pressure for the desorption of the ozone is generated in a water jet gas compressor.
- the oxygen used to generate ozone is taken from an upright tank 1 in liquid form, evaporated in the evaporator 2, its pressure is reduced to a pressure of 0.5 to 2 bar (absolute) in the pressure reducer 3, and fed into the ozone generator 4.
- the ozone-oxygen mixture produced in the ozone generator 4 is fed into the pressure swing adsorber 6 by the circulating blower 5.
- the pressure swing adsorber 6 consists of at least two silica gel-packed containers which are cycled at intervals of 0.5 to 5 minutes. Ozone is adsorbed in one of the containers, while the oxygen passes through the container and is returned cleanly and without contamination for ozone generation via the pipe 7.
- ozone is desorbed in the other container under a lower than atmospheric pressure.
- the vacuum is generated by a water jet gas compressor 8. This generates a vacuum of better than 0.2 bar (absolute) on the suction side toward the pressure swing adsorber 6.
- the pressure of the water jet which serves as the flowing medium is increased by the pump 9 so much that the water jet gas compressor 8 reaches the required suction capacity.
- the directions of flow are indicated by the arrows 10.
- the desorbed gas which consists of ozone and residual oxygen, which is drawn off from the pressure swing absorber 6, is passed through an equalizing tank 11 under vacuum before it is mixed with water as the flowing medium in the water jet gas compressor 8.
- This equalizing tank 11 has three times the volume of one container of the pressure swing adsorber 6 and is filled with silica gel 12 to one-third.
- the silica gel 12 is arranged on the outlet side of the equalizing tank 11.
- the equalizing tank 11 causes a reduction of the pressure rise at the beginning of the desorption phase and equalization of the ozone concentration in the desorbed gas before it is introduced into the reaction medium.
- the ozone generated in the ozone generator 4 is consequently separated from the oxygen practically completely due to the adsorption on silica gel in the pressure swing adsorber. It is subsequently desorbed by applying vacuum. It is adsorbed and stored again--by the silica gel 12 of the equalizing tank 11--in the third step. Finally, it is uniformly released into the flowing medium which serves as the transport or reaction medium in the fourth and last step.
- the process according to the present invention is not bound to the use of water jet gas compressors to generate vacuum.
- the vacuum can also be generated by an injector and a gaseous medium serving as the flowing medium.
- the vacuum can also be generated by a pump, and the flowing medium is used only as a transport medium for the ozone.
- the volume of the equalizing tank is dependent primarily on the suction pressure applied. Its volume is usually two to four times the volume of one container of the pressure swing adsorber 6.
- the equalizing tank 11 can also be filled with silica gel to more than one-third. In general, one should seek to prevent the pressure peak of the desorbed gas from exceeding 0.6 bar (absolute) and the ozone concentration from exceeding 160 g ozone/m 3 gas relative to the technological state at the beginning of the desorption phase, i.e., when switching over from adsorption to desorption as well as during the reduction of the pressure in the particular container of the pressure swing adsorber 6 through the combination of the suction pressure applied, which is generally lower than 0.2 bar (absolute), of the free volume of the equalizing tank 11 and of the volume of the silica gel 12. If these limited values are not exceeded, it is also achieved that the ozone is released at a highly uniform concentration after the equalizing tank 11.
- Ozone is produced from oxygen in ordinary ozone generators 4 and is separated from the nonconverted oxygen in a pressure swing adsorber 6 by adsorbing it there on an adsorbent mass.
- the desorption can be carried out with a scavenging gas or vacuum.
- the vacuum method has the advantage that the ozone is not mixed with a scavenging gas, but is mixed in pure form to a flowing medium and is reacted.
- pressure and concentration peaks occur during the desorption phase under vacuum, especially at the beginning of the desorption phase. This is undesirable when uniform ozone supply for material treatment is important.
- the ozone is passed through an equalizing tank 11 under vacuum; this equalizing tank is arranged between the pressure swing adsorber and the vacuum generating means and is filled at least partially with silica gel 12.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Oxygen, Ozone, And Oxides In General (AREA)
- Separation Of Gases By Adsorption (AREA)
Abstract
Description
Claims (6)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3434169A DE3434169C2 (en) | 1984-09-18 | 1984-09-18 | Process for producing ozone |
| DE3434169 | 1985-09-18 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US4604279A true US4604279A (en) | 1986-08-05 |
Family
ID=6245655
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US06/773,030 Expired - Fee Related US4604279A (en) | 1984-09-18 | 1985-09-06 | Process for producing ozone |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US4604279A (en) |
| EP (1) | EP0178415A3 (en) |
| JP (1) | JPS6172602A (en) |
| DE (1) | DE3434169C2 (en) |
| NO (1) | NO853316L (en) |
| ZA (1) | ZA857148B (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5039314A (en) * | 1989-06-26 | 1991-08-13 | Voest-Alpine Industrienlagenbau Gesellschaft M.B.H. | Method for producing oxygen and/or ozone |
| US5785738A (en) * | 1994-12-27 | 1998-07-28 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Process and plant for treatment of a gas mixture including ozone |
| US5888271A (en) * | 1996-03-01 | 1999-03-30 | Mitsubishi Denki Kabushiki Kaisha | Ozone storing method and ozone storage system |
| US6030598A (en) * | 1997-06-11 | 2000-02-29 | Air Products And Chemicals, Inc. | Process for producing a gaseous product |
| RU2179149C2 (en) * | 1999-08-04 | 2002-02-10 | Открытое акционерное общество криогенного машиностроения | Method and apparatus for producing ozone-gas mixture |
| US6530976B2 (en) | 2000-03-02 | 2003-03-11 | The Kansai Electric Power Co., Inc. | Ozone storage method and ozone storage apparatus |
| US20040028576A1 (en) * | 2002-04-25 | 2004-02-12 | The Boc Group Inc. | Ozone production processes |
| US20050274125A1 (en) * | 2004-06-09 | 2005-12-15 | Giacobbe Frederick W | Methods of dissolving ozone in a cryogen |
| US20080241052A1 (en) * | 2007-03-29 | 2008-10-02 | Hooper David M | Apparatus, method and system for delivering oxygen-ozone |
| US20090010835A1 (en) * | 2007-07-03 | 2009-01-08 | Amarante Technologies, Inc. | Systems and methods for generating and storing ozone |
| US20100005961A1 (en) * | 2006-11-24 | 2010-01-14 | Iwatani Corporation | Method and apparatus for condensing ozone gas |
| US20100189635A1 (en) * | 2009-01-23 | 2010-07-29 | Air Products And Chemicals, Inc. | Pressure Swing Adsorption Cycle for Ozone Production |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3603900A1 (en) * | 1985-02-13 | 1986-08-21 | Mitsubishi Denki K.K., Tokio/Tokyo | DRINKING WATER PURIFICATION DEVICE |
| FR2580271B1 (en) * | 1985-04-16 | 1994-07-08 | Air Liquide | OZONE PRODUCTION PROCESS |
| DE3632937A1 (en) * | 1986-09-27 | 1988-03-31 | Bbc Brown Boveri & Cie | METHOD FOR PRODUCING OZONE |
| JP3769742B2 (en) * | 1995-11-14 | 2006-04-26 | 石川島播磨重工業株式会社 | Control method of ozone generator |
| JP3769741B2 (en) * | 1995-11-14 | 2006-04-26 | 石川島播磨重工業株式会社 | Ozone concentration storage device and control method thereof |
| WO2010010610A1 (en) * | 2008-07-23 | 2010-01-28 | 岩谷産業株式会社 | Method of concentrating ozone gas and apparatus therefor |
| JP5888908B2 (en) | 2011-09-09 | 2016-03-22 | 岩谷産業株式会社 | Concentration method of ozone gas |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3921002A (en) * | 1974-04-22 | 1975-11-18 | Martin Marietta Corp | Ozone generator |
| US4280824A (en) * | 1978-12-14 | 1981-07-28 | Linde Aktiengesellschaft | Process for providing a feed gas for a chemical reaction and for the separation of a gaseous reaction product |
| DE3230922A1 (en) * | 1982-08-20 | 1984-02-23 | Messer Griesheim Gmbh, 6000 Frankfurt | METHOD FOR TREATING SUBSTANCES WITH OZONE |
| US4468237A (en) * | 1982-10-19 | 1984-08-28 | Union Carbide Corporation | Pressure swing adsorption with direct and indirect pressure equalizations |
| US4482361A (en) * | 1983-01-14 | 1984-11-13 | Union Carbide Corporation | Pressure swing adsorption process |
| US4515605A (en) * | 1979-12-07 | 1985-05-07 | Toray Industries, Incorporated | Separation process for a gas mixture |
| US4528000A (en) * | 1982-01-05 | 1985-07-09 | Mcgill Incorporated | Fuel conditioning process |
-
1984
- 1984-09-18 DE DE3434169A patent/DE3434169C2/en not_active Expired
-
1985
- 1985-08-16 EP EP85110259A patent/EP0178415A3/en not_active Ceased
- 1985-08-22 NO NO853316A patent/NO853316L/en unknown
- 1985-09-06 US US06/773,030 patent/US4604279A/en not_active Expired - Fee Related
- 1985-09-18 JP JP60204585A patent/JPS6172602A/en active Pending
- 1985-09-18 ZA ZA857148A patent/ZA857148B/en unknown
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3921002A (en) * | 1974-04-22 | 1975-11-18 | Martin Marietta Corp | Ozone generator |
| US4280824A (en) * | 1978-12-14 | 1981-07-28 | Linde Aktiengesellschaft | Process for providing a feed gas for a chemical reaction and for the separation of a gaseous reaction product |
| US4515605A (en) * | 1979-12-07 | 1985-05-07 | Toray Industries, Incorporated | Separation process for a gas mixture |
| US4528000A (en) * | 1982-01-05 | 1985-07-09 | Mcgill Incorporated | Fuel conditioning process |
| DE3230922A1 (en) * | 1982-08-20 | 1984-02-23 | Messer Griesheim Gmbh, 6000 Frankfurt | METHOD FOR TREATING SUBSTANCES WITH OZONE |
| US4468237A (en) * | 1982-10-19 | 1984-08-28 | Union Carbide Corporation | Pressure swing adsorption with direct and indirect pressure equalizations |
| US4482361A (en) * | 1983-01-14 | 1984-11-13 | Union Carbide Corporation | Pressure swing adsorption process |
Cited By (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5039314A (en) * | 1989-06-26 | 1991-08-13 | Voest-Alpine Industrienlagenbau Gesellschaft M.B.H. | Method for producing oxygen and/or ozone |
| US5785738A (en) * | 1994-12-27 | 1998-07-28 | L'air Liquide, Societe Anonyme Pour L'etude Et L'exploitation Des Procedes Georges Claude | Process and plant for treatment of a gas mixture including ozone |
| US5888271A (en) * | 1996-03-01 | 1999-03-30 | Mitsubishi Denki Kabushiki Kaisha | Ozone storing method and ozone storage system |
| US6030598A (en) * | 1997-06-11 | 2000-02-29 | Air Products And Chemicals, Inc. | Process for producing a gaseous product |
| RU2179149C2 (en) * | 1999-08-04 | 2002-02-10 | Открытое акционерное общество криогенного машиностроения | Method and apparatus for producing ozone-gas mixture |
| US6530976B2 (en) | 2000-03-02 | 2003-03-11 | The Kansai Electric Power Co., Inc. | Ozone storage method and ozone storage apparatus |
| US20030145727A1 (en) * | 2000-03-02 | 2003-08-07 | Akira Murai | Ozone storage method and ozone storage apparatus |
| US20040028576A1 (en) * | 2002-04-25 | 2004-02-12 | The Boc Group Inc. | Ozone production processes |
| US6916359B2 (en) | 2002-04-25 | 2005-07-12 | The Boc Group, Inc. | Ozone production processes |
| US7392657B2 (en) | 2004-06-09 | 2008-07-01 | American Air Liquide, Inc. | Methods of dissolving ozone in a cryogen |
| US20050274125A1 (en) * | 2004-06-09 | 2005-12-15 | Giacobbe Frederick W | Methods of dissolving ozone in a cryogen |
| US20100005961A1 (en) * | 2006-11-24 | 2010-01-14 | Iwatani Corporation | Method and apparatus for condensing ozone gas |
| US8012241B2 (en) * | 2006-11-24 | 2011-09-06 | Iwatani Corporation | Method and apparatus for condensing ozone gas |
| KR101339494B1 (en) * | 2006-11-24 | 2013-12-10 | 이와다니산교가부시기가이샤 | Method of concentrating ozone gas and apparatus therefor |
| US20080241052A1 (en) * | 2007-03-29 | 2008-10-02 | Hooper David M | Apparatus, method and system for delivering oxygen-ozone |
| US7588749B2 (en) * | 2007-03-29 | 2009-09-15 | Minimus Spine, Inc. | Apparatus, method and system for delivering oxygen-ozone |
| US20090010835A1 (en) * | 2007-07-03 | 2009-01-08 | Amarante Technologies, Inc. | Systems and methods for generating and storing ozone |
| US7588750B2 (en) * | 2007-07-03 | 2009-09-15 | Amarante Technologies, Inc. | Systems and methods for generating and storing ozone |
| US20100189635A1 (en) * | 2009-01-23 | 2010-07-29 | Air Products And Chemicals, Inc. | Pressure Swing Adsorption Cycle for Ozone Production |
| US8029603B2 (en) * | 2009-01-23 | 2011-10-04 | Air Products And Chemicals, Inc. | Pressure swing adsorption cycle for ozone production |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6172602A (en) | 1986-04-14 |
| DE3434169A1 (en) | 1986-04-24 |
| EP0178415A3 (en) | 1986-12-30 |
| EP0178415A2 (en) | 1986-04-23 |
| NO853316L (en) | 1986-03-19 |
| DE3434169C2 (en) | 1987-01-02 |
| ZA857148B (en) | 1986-05-28 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: MESSER GRIESHEIM GMBH, FRANKFURT/MAIN, GERMAY A CO Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:LEITZKE, ORTWIN;WOLF, EWALD;REEL/FRAME:004546/0879 Effective date: 19850727 Owner name: MESSER GRIESHEIM GMBH, GERMANY Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:LEITZKE, ORTWIN;WOLF, EWALD;REEL/FRAME:004546/0879 Effective date: 19850727 |
|
| REMI | Maintenance fee reminder mailed | ||
| LAPS | Lapse for failure to pay maintenance fees | ||
| STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
| FP | Lapsed due to failure to pay maintenance fee |
Effective date: 19900805 |